We propose to develop patient study methods for determining local cerebral blood volume (LCBV), local cerebral blood flow (LCBF), local cerebral glucose utilization, and other physiological data localized throughout the brain in three-dimensions using transverse section scanning of radioactive indicators administered intravenously. Once validated, these methods will be applied to enhance the diagnosis and management of patients with brain tumors, stroke, head injury, and metabolic encephalopathies and to aid our understanding of normal cerebral physiology in man.